I talked to my professor and she doesn't believe in a literal revelation?

My professor is a Christian and she believes that John wrote revelation as a metaphor for the state the world has been in since the first coming of Jesus. She doesn't believe that there will be a tribulation, a mark of the beast or only one antichrist who will rule the world. She believed that John used these things as a metaphor because he is the most metaphoric biblical writer. I want to know what other Christians think of this idea.